It is generally known to provide insulated panels or walls for temperature controlled storage areas (e.g. walk-in coolers, etc.) or for other structures or enclosures where a thermal boundary is desired. Such known walls or panels typically include wall or paneling structures where a layer of an insulation material is installed (e.g. blankets, sheets, etc.) within a cavity of a wall during construction of the wall or structure, or is applied (e.g. spraying a foam material, etc.) to a surface of the wall or structure after construction is complete. Such insulation panels typically have frame members that require field application of a sealant at the joints of the frame members during assembly of the temperature controlled storage areas to prevent condensation from infiltrating the frame members and to reduce heat loss through the joint. Such field application of a sealant is time-consuming, sloppy and often results in varying degrees of effectiveness based upon the skill and expertise of the installer. Also, frame members are typically made from a wood material (e.g. ‘two by four’ lumber, etc.) due to its relatively low cost and relatively good thermal insulation properties (when compared to metallic frame members). However, such two by four wood frame members usually do not provide the same thermal insulation performance as the body of the insulation panels. Accordingly, it would be desirable to provide a structural insulated panel system having frame members that include an improved joint sealing system, and/or provide improved thermal insulation performance with the benefit of having a reduced weight.